Testing for Twice-Exceptional Child

By Inderbir Kaur Sandhu, Ph.D

Q:
How is a child with ADHD and dyslexia tested for being gifted? This is for a nine year old.

A:
This is a very valid question. To test for giftedness, usually a
combination of methods is used; the main being a cut-off score on a
standardised IQ test. I will talk about dyslexia first. Many children
with dyslexia are noticed to be of average or above-average
intelligence. In relation to testing for giftedness, I would explain the
WISC-IV for a dyslexic child. This test often shows particular profiles
for dyslexic readers, with a working memory score that is often
significantly lower than most other scores, and in some cases a
processing speed score that is also significantly lower than verbal
comprehension and/or perceptual reasoning scores. However, this may be
eliminated using the General Ability Index (GAI) rather than the Full
Score IQ (FSIQ), which eliminates working memory and processing speed
scores.

Because dyslexia is a processing disorder and NOT a cognitive disorder,
once provisions (intervention) are to facilitate a child's somewhat
different way of learning, these kids are very capable of performing
just as anyone else would which includes doing well on an IQ test.
However, it appears that timed tests may be harder due to the delay in
cognitive processing.

As an example of scores on the WISC-IV, if the child has a reading
disorder, it would be observed that there may be low scores on
Vocabulary, Letter-Number Sequencing, Information and Arithmetic. Now,
the lower scores on Vocabulary and Information could simply reflect that
(in part), the child may have a deficiency in information generally
which is commonly acquired through reading (which a dyslexic child may
lack). As for low scores in Letter-Number Sequencing, it may indicate
problems in working memory.

As for children with ADHD, they appear to have significantly lower
scores in Coding (Processing Speed) and Arithmetic (Working Memory)
subtests. This is consistent with research evidence indicating that
children with ADHD perform less well on Processing Speed and Working
Memory measures.

In combination for both ADHD and Dyslexia, a child would typically
perform less well on Processing Speed and Working Memory and are found
to have a lower FSIQ.

To conclude, after testing for intelligence and interpreting the
results, the teacher, psychologist, or anyone else concerned, should
keep in mind the areas that may be under-represented because of this
disability. A full assessment that takes into account the above factors
should be catered for. An IEP has to be prepared for both the strengths
and weaknesses (twice-exceptional if determined as gifted). Hope that
helps in your understanding.